The use of communication systems through which to communicate data between two or more locations is a necessary adjunct of modem society. In a communication system, data sourced, or originated, at a sending station is communicated, by way of a communication channel to a receiving station. The sending station forms a first endpoint, and the receiving station forms a second endpoint between which the data is communicated. When the endpoints include both sending and receiving stations, two-way communication of data is permitted.
The introduction, and popular usage, of new types of communication systems has been made possible as a result of advancements in communication technologies. Through the use of such communication systems, for example, data can be communicated between the endpoints at higher data transmission rates. And, new types of communication services, requiring data transmissions at the increased rates, or throughputs, have been made possible, as a result. Advancements in digital communication techniques are amongst the advancements in communication technologies that have permitted the introduction of new types of communication services.
A radio communication system is exemplary of a communication system in which communication-technology advancements have been implemented. In a radio communication system, a radio link is used to form at least a part of a communication path extending between communication endpoints and upon which a communication channel is defined. Because of the radio link, communications in a radio communication system inherently provides improved communication mobility relative to conventional, wireline communication systems. Wirelines, otherwise required upon which to form the communication path, are obviated. Communications are effectual, as a result, from, and between, endpoints positioned at locations at which the use of a conventional, wireline communication system would be impractical.
A cellular communication system is a type of radio communication system that is popularly utilized. A cellular communication system is a multi-user system, the implementation of which has been made possible due to advancements in communication technologies.
Various standards have been promulgated relating to various types of cellular communication systems, and various types of cellular communication systems have been constructed corresponding to such standards. Successive generations of cellular communication systems have been proposed, some of which have been implemented. So-called, first-generation communication systems generally rely upon analog communication techniques. So-called, second-generation communication systems generally make use of digital communication techniques. And, so-called, third-generation communication systems also make use of digital communication techniques. Third-generation systems, amongst other things, also provide for multiple data-rate communications. Additional proposals are being set forth for a subsequent-generation communication system. Generally, such proposals pertain to packet-based radio communication systems in which packet-formatted data is communicated.
Such proposals include proposals to the IETF (Internet Engine Task Force). In at least one proposal, communications between two endpoints, such as a mobile node and a correspondent node, are effectuated by setting up a bearer between the endpoints. The term “bearer” is used, generally, to refer to a connection, at least upon a radio link extending to the mobile node from a network part of the communication system. And, the bearer generally refers to an entity formed by all factors that affect data transmission upon the radio link extending to the mobile node. For instance, the data transmission rate, delay, and bit error ratio are all factors that are determinative of the bearer. The procedure and process of setting up of the bearer is sometimes referred to as a bearer setup. And, a bearer manager is a network entity, located, for instance, at an access network, that controls the bearer setup procedures.
Existing proposals relating to mechanisms and procedures associated with bearer setup require that a direct interface be utilized to route a bearer setup request to an appropriate bearer manager. For instance, when the network part of the communication system includes application servers, the direct interface is required to be positioned between an application server and the bearer manager. This requirement lacks scalability.
For instance, when a mobile node with which a bearer is to be formed is in a visited network, and an application server which forms the home application server of the mobile node initiates the bearer setup, the application server must know the address of the bearer manager in the visited network. As the mobile node could reside in any visited network, the application server must, therefore, have knowledge of the addresses of all the bearer managers in all of the visited networks that may be visited by the mobile node. When the application server that initiates the bearer setup is located in the visited network at which the mobile node is located, a direct interface between the visited application server and the bearer manager still may not exist, particularly when the application service provider and the transport network provider are not the same. And, even when the application service and transport network providers are the same, there may be multiple bearer managers serving different endpoints in the visited network. The application server in the visited network still must need to be cognizant of which bearer manager should be contacted for a particular endpoint.
As, therefore, the existing mechanisms and protocols are inadequate to permit efficient bearer setup, an improved manner by which to facilitate bearer setup is required.
It is in light of this background information related to bearer setup in a radio communication system that the significant improvements of the present invention have evolved.